Add check on Cube Completeness for Cube textures and improve the efficiency of checks associated wi…

Source/core/html/canvas/WebGLTexture.cpp

Index: Source/core/html/canvas/WebGLTexture.cpp
diff --git a/Source/core/html/canvas/WebGLTexture.cpp b/Source/core/html/canvas/WebGLTexture.cpp
index 15cb7471435e966a58880340bf897adcb940c4a4..ddc6f0041e61810062357d8e53666340924ae9fb 100644
--- a/Source/core/html/canvas/WebGLTexture.cpp
+++ b/Source/core/html/canvas/WebGLTexture.cpp
@@ -318,6 +318,7 @@ void WebGLTexture::update()
         }
     }
     m_isComplete = true;
+    bool isCubeComplete = true;

[Ken Russell (switch to Gerrit), 2013/06/06 23:16:43]

Please make isCubeComplete a member of the WebGLTexture class
(m_isCubeComplete). It needs to be checked in at least one other place.

     const LevelInfo& first = m_info[0][0];
     GC3Dint levelCount = computeLevelCount(first.width, first.height);
     if (levelCount < 1)
@@ -327,7 +328,10 @@ void WebGLTexture::update()
             const LevelInfo& info0 = m_info[ii][0];
             if (!info0.valid
                 || info0.width != first.width || info0.height != first.height
-                || info0.internalFormat != first.internalFormat || info0.type != first.type) {
+                || info0.internalFormat != first.internalFormat || info0.type != first.type
+                || (m_info.size() > 1 && info0.width != info0.height)) {
+                if (m_info.size() > 1)
+                    isCubeComplete = false;
                 m_isComplete = false;
                 break;
             }
@@ -347,34 +351,17 @@ void WebGLTexture::update()
             }
         }
     }
-    m_isFloatType = false;
-    if (m_isComplete)
-        m_isFloatType = m_info[0][0].type == GraphicsContext3D::FLOAT;
-    else {
-        for (size_t ii = 0; ii < m_info.size(); ++ii) {
-            if (m_info[ii][0].type == GraphicsContext3D::FLOAT) {
-                m_isFloatType = true;
-                break;
-            }
-        }
-    }
-    m_isHalfFloatType = false;
-    if (m_isComplete)
-        m_isHalfFloatType = m_info[0][0].type == GraphicsContext3D::HALF_FLOAT_OES;
-    else {
-        for (size_t ii = 0; ii < m_info.size(); ++ii) {
-            if (m_info[ii][0].type == GraphicsContext3D::HALF_FLOAT_OES) {
-                m_isHalfFloatType = true;
-                break;
-            }
-        }
-    }
+    m_isFloatType = m_info[0][0].type == GraphicsContext3D::FLOAT;
+    m_isHalfFloatType = m_info[0][0].type == GraphicsContext3D::HALF_FLOAT_OES;

[bajones, 2013/06/05 17:29:00]

This feels unrelated to the cubemap change. What's the reason for changing this
logic?

[Jun Jiang, 2013/06/06 01:19:48]

This change is to optimize the check on whether the texture type is GL_FLOAT or
GL_HALF_FLOAT, which will be used to judge whether RGBA(0,0,0,1) should be
returned when Linear filter is used.

As Kenneth mentioned in https://codereview.chromium.org/14860016/, it is not
necessary to scan all the faces of the Cube to check the type and checking only
the first is enough. If two faces have different types, it is not Cube complete
and m_needToUseBlackTexture will be true. If all faces have the same type, it
may be redundant to check all the faces.

When adding the check for Cube completeness, I optimize the check associated
with the OES_texture_{half_}float_linear extension as well instead of fire a
separate bug.

 
     m_needToUseBlackTexture = false;
     // NPOT
     if (m_isNPOT && ((m_minFilter != GraphicsContext3D::NEAREST && m_minFilter != GraphicsContext3D::LINEAR)
                      || m_wrapS != GraphicsContext3D::CLAMP_TO_EDGE || m_wrapT != GraphicsContext3D::CLAMP_TO_EDGE))
         m_needToUseBlackTexture = true;
+    // If it is a Cube texture, check Cube Completeness first
+    if (m_info.size() > 1 && !isCubeComplete)
+        m_needToUseBlackTexture = true;
     // Completeness
     if (!m_isComplete && m_minFilter != GraphicsContext3D::NEAREST && m_minFilter != GraphicsContext3D::LINEAR)
         m_needToUseBlackTexture = true;